A little while back I wrote up a blog post on how Microsoft paint can be used to identify the RGB values for a color and then those can be added into Visio (http://www.systemcentercentral.com/BlogDetails/tabid/143/IndexID/94754/Default.aspx). You can use the eyedropper (highlighted below) to sample the color and add it as a custom color.
Savision Live Maps can also match these RGB values like Visio does. The graphic below shows how a fill can be changed to have a custom color which can use the same RGB values gathered by Microsoft paint!
This approach makes it really simple to use graphics from a variety of sources and create a dashboards which has a similar graphical look and feel of the customer’s existing website or documentation.